This guide will tell you everything you need to know about how drains get blocked, how to reduce blocked drains and what to do about blocked drains when they do happen. It’s based on our experience as home-owners and DIYers, real-world testing and some internet research.

Best Drain Unblockers UK

Why drains get blocked

Drains are meant to treat water and water only. If anything else goes into them, they will almost certainly become blocked. Given that it’s almost impossible to ensure that only water goes into drains, you need to focus on managing your drains to minimize blockages and treating them when they do occur, rather than trying to prevent them completely.

The main causes of blocked drains

If you do your best to avoid the common causes of blocked drains, you’ll reduce the number of times you need to unblock them. With that in mind, here’s a list of the most common sources of drain blockages.

Damage to pipes

This may seem an odd one, but you might be surprised how often it’s a problem. Essentially if your pipes are damaged then they can become filled with dirt which ultimately causes a blockage. Also, if there are any trees or bushes in the vicinity, then their roots can get into your pipes making the matter worse. The only cure for this is to sort the damaged piping.

Grease and fat

Maybe you’ve read about fatbergs? If not you can do an internet search on the topic, but be prepared. The results aren’t pretty.

Emptying grease and fat down your drain may be convenient in the short-term but it causes all kinds of problems in the long-term. Put it in the bin instead. A lot of cooking oils, even liquid ones, will solidify if you put them in the fridge for a while, you can then wrap them in a tissue and dispose of them in the usual way. Alternatively, put them in a non-recyclable container (or both). Whatever you do keep them out of your drains.

Similarly, a lot of skin care products contain some form of grease or fat, although it’s unlikely to be marketed as such. If its name includes words like “serum”, “oil”, “cream” or anything suggesting moisturizing qualities, it should be kept well away from your drains. This means that if you put it on with your hands you should wipe your hands clean rather than washing them (or wipe them and then wash them).

Clogged Drain

Best Drain Unblockers UK

Personal hygiene products

In the UK, it’s fine to put toilet paper down the toilet. Anything else, however, goes in the bin. Wrap it in something first if you need to, but never put it down your toilet. (Similarly, kitchen roll also goes in the bin).

Hair

You don’t need to shave your head, you don’t even need to wear a shower cap (or bath cap). We do, however, suggest giving your hair a good brush before you get into the bath or shower. We’d also suggest that you invest in a hair trap for your bath and/or shower. In fact, we’d recommend investing in a decent one as it will be much pleasanter to use. 

On a similar note, if you wash any pets in the bath or shower, try to brush them first. We understand that this might not be feasible if they’re covered in mud, but if you can brush them then your drains will appreciate it. 

Similarly, do your best to remove pet hair before you put anything in the washing machine. It’s not good for the machine and it’s definitely not good for your drain.

Dirt

Whether or not this one is avoidable depends very much on your lifestyle. If you’re in the habit of having muddy pets jump straight into the bath or shower (or sink) then you might want to start using a towel to get off the worst of the mud before you turn on the water. If you think this is more hassle than it’s worth, then you’ll just have to accept the fact that you’ll be unblocking your drains more often than would otherwise be necessary.

What you can and should avoid, however, is excess food waste landing up in your kitchen sink (or dishwasher). Hopefully, you are already scraping your plates before putting them in for washing. Resist any temptation to empty the likes of tea leaves and coffee granules into the sink and wash them away. Either reuse them or put them in the recycling/bin.

Minerals

If you live in a limescale-area then regularly unblocking your drains is just going to be a fact of life. Even if you don’t, mineral build-up will probably be an issue to some extent.

Soap scum

This is the one most people will find practically unavoidable. Even the highest-quality cleaning products will generally leave some form of residue and, over time, this can block your drains. The good news is that this should be a fairly minor problem.

How to tell if a drain is blocked

The most obvious way to tell if a drain is blocked is that the water won’t drain properly. Unless the drain is completely blocked it will generally drain away eventually, but it will be very slow. Another sign is a bad smell.

How to keep a drain clear

The best way to deal with drain blockages is to stop them from happening in the first place. In case we haven’t made ourselves clear, the best way to do this is to be very careful what gets into them. You can, however, add to this by giving your drains a basic but effective clean once a week.

There are various ways you can do this but our favourite is to put a squirt of washing-up liquid into the plug and then slowly pour boiling water down it. You want at least a litre, more is better. The reason this is good is that the washing up liquid will help to break down grease and fat and then the hot water cleans the pipes and helps to flush everything away.

Pro tip - if you have a ceramic sink, warm it up a bit before you pour the boiling water, otherwise, it will crack.

DIY how to unblock a drain

Let’s say that, despite everything you have a blockage and you’d like to try unblocking it without having to go out and buy chemical cleaners or cleaning tools. You may find you have what you need in your cupboards.

Washing up liquid and water

Start with the easy option, which is often also the best for getting rid of blockages caused by fat and grease. If the drain is blocked, however, you will probably want to increase the amount of washing up liquid you use. Try two squirts instead of one and also double the amount of boiling water.

Baking soda, vinegar and water

This treatment is often recommended on the internet and it can work very well for blockages caused by something other than fat or grease. Start with boiling water, lots of it, then add half a cup (125g) of baking soda/bicarbonate of soda (either will do) and let it sit for about 5 minutes. Then chase it with a cup (250ml) of vinegar, preferably white, and let that sit for about 15 minutes. Then chase that with more hot water.

Caustic soda

Wearing gloves and safety goggles, dilute 3 cups (750g) of caustic soda in 3 litres of cold water. If necessary stir with something wooden that you won’t use for cooking. Pour this slowly and carefully down the drain, avoid splashes. Leave for 30 minutes and then flush with 4 litres of boiling water.

Sink Unblocker

Best sink unblocker

The nature of kitchen sinks means that they can often use a little extra care. We’d recommend using a drain stick. These basically use friendly enzymes to break down grease and fat so that they can be carried away with the water instead of blocking up your drains. 

There are plenty of options on the market. Our favourite is Ecozone as it does the job and has solid environmental credentials. 

Pro tip, sometimes these sticks slip down the piping so you can’t see them. Ignore this. They will continue to work for as long as they are supposed to work then they will dissolve. If you add another stick while the first one is still in the pipe, you may actually create a blockage instead of keeping your drains clear.

If you still need to clear your sink drain, then we’d suggest the Ecozone Kitchen Drain Unblocker as this is formulated for grease and fat which is the usual problem with kitchen drains. It does a very decent job and is about as environmentally-friendly as you can get.

Best liquid drain unblocker

If you’re looking for a liquid drain unblocker specifically for hair, then we’d suggest the HG Hair Unblocker and if you’re looking for an all-round liquid drain unblocker, then we’d suggest the HG Liquid Drain Unblocker for everything except kitchen sinks and the HG Kitchen Drain Unblocker for any situations where you need something more powerful than the Ecozone product we previously recommended.

For the record, we have nothing to do with HG, it’s just they’ve really focused on liquid drain unblockers and, in our opinion, literally have the best on the market.

Best powder drain unblocker

We’ve only found one powder drain unblocker we’d be happy to recommend and that’s Duzzit Drain Away. This stuff is extremely strong so you need to handle it with great care. You also need to be prepared for a very strong-smelling vapour. Do not inhale this. In fact, if you can wear a face mask (plus gloves and goggles).

One packet will generally clear any drain which has been kept reasonably well-maintained. If your drains are in a bad state you may need to use two or even three packets, but that would only be for drains which are in a really bad way.

Best drain unblocker for limescale

If you are in a limescale area then it's a safe bet that your drains are going to suffer from the effects regardless of how well you treat them. Our favourite drain unblocker for limescale is the Kilrock MEGA-K descale. This really is a mega-cleaner so treat it with respect. Use gloves, safety goggles and a face mask and pay attention to ventilation because it gives off some serious fumes.

For completeness, this product doesn’t always fizz like it says it will, but regardless it does always seem to work. You may not initially notice this, however, since you seem to need to flush with water to finish it off. If you’re using it on a toilet, you may also have to give the bowl a quick brush before you flush, but it will be an easy task because this stuff really is as good as we say.

Best drain unblocker tools

Liquid drain unblockers and powder drain unblockers are generally the most convenient options. Sometimes, however, you’re going to have to get more “hands-on” and get to grips with drain unblocker tools. 

Luigi is probably best known for its toilet plunger and we definitely recommend it, but unblocking drains you want their sink and drain plunger. This looks a bit flimsy, but in this case, looks are deceptive. It can really work up some suction power and will deal with a lot of blockages.

Our other recommendation is the Liumy drain-cleaning kit. It’s a 6-piece set of tools designed to slide down your plughole and deal with various kinds of blockages. They’re at the upper end of the DIY price range for these kinds of tools, but they’re still an awful lot more economical than calling a plumber.

In short

If you are careful about what you put down your drains, then a regular weekly clean should be all they ever need, unless you live in a limescale area. If, however, your drains become blocked then there are plenty of affordable options you can try before you go to the expense of calling a plumber.